Persona chat simulator
The fastest way to know whether a chatbot persona actually holds up is to talk to it. Write a system prompt that defines the role, tone, knowledge, and boundaries, then have a real multi-turn conversation with it using your own API key. The simulator sends the full history each turn, so the bot remembers context exactly as it would in production — which means you can probe it with the awkward, off-topic, and adversarial messages your real users will send, and fix the persona before you ship it.
How it works
You define the persona in a system prompt and pick a provider, model, and temperature. As you chat, the tool maintains the conversation history and sends it in full on every turn — OpenAI’s messages array, Anthropic’s messages endpoint with a top-level system field, or Gemini’s contents with a system instruction — so the persona has genuine memory of the exchange. Replies appear with loading and error states handled, and a clear button resets the history for a fresh test. Everything runs in your browser: the key and the conversation are never stored or sent anywhere except the direct provider call.
Tips and notes
- Test like a hostile user. Off-topic questions, “ignore your instructions,” and emotional messages reveal where a persona breaks.
- Fix in the system prompt, then restart. Persona drift is cured by explicit scope and refusal rules — change them and start a fresh chat to verify.
- Match shipping temperature. A support bot wants low temperature for consistency; a character can take more.
- Watch the boundaries. Confirm the persona refuses what it should and stays in role across many turns, not just the first.